U.S. Pat. No. 3,238,898 shows and describes a typical locking mechanism which is in use today for holding individual hopper doors of a railroad hooper car in closed relation. The locking pawls of such mechanisms used on a pair of hopper doors transversely spaced on a hopper car, must be separately operated to disengage the camming mechanisms so that they, in turn, can be rotated out of interlocking engagement with the hooks which are fastened to the hopper door frames adjacent the marginal edges of the hopper doors. Further, the pawls must be operated from opposing sides of the hopper car. This requires an operator on either side of the car or, if a single operator is in attendance, then the operator must first disengage one pawl from one side of the hopper car and then go to the other side of the car to disengage the other pawl. This is not only time consuming and expensive, but endangers the life of a single operator who is forced to walk between a pair of coupled railroad cars to disengage the pawls. The invention is designed to overcome this problem by providing a locking mechanism which can be controlled by a single operator from either side of a railroad hopper car.
Briefly stated, the invention is in a locking mechanism for a pair of hopper doors which are laterally spaced side-by-side transversely of a railroad hopper car. At least one L-shaped cam with a handle, is rotatably mounted on each of the pair of hopper doors. At least one hook is fixedly disposed adjacent each of the cams for interlocking engagement with the cams to hold the hopper doors in closed relation against a hopper door frame which is secured to each of the hoppers of the railroad hopper car. Means are provided for mounting the pair of hopper doors for unitary rotation to and from the hopper door frames and for mounting the cams for unitary rotation, into and out of interlocking relation with the hooks. A locking pawl is carried by each of the hopper doors for interlocking engagement with the distal end of each handle to keep the cams from rotating out of interlocking engagement with the hooks. Means are supplied for mounting the pawls on the hopper doors for unitary rotation, so that a single operator can disengage, (I) the pawls from the handles, and (II) the cams from the hooks of both hopper doors from either side of the railroad car.